Syphilis is treated with antibiotics, which can be administered as injections, tablets, or capsules. The preferred treatment at all stages of syphilis is penicillin, which can kill the bacteria that cause syphilis. If you are allergic to penicillin, your doctor may suggest another antibiotic or recommend penicillin desensitization. The recommended treatment for primary, secondary, or early-stage latent syphilis is a single injection of penicillin. If you have had syphilis for longer than a year, you may need additional doses. Pregnant women with syphilis at any stage should be treated with penicillin, as it is the only therapy with documented efficacy for syphilis during pregnancy. People treated for syphilis should avoid sexual contact with new partners until their sores completely heal. They should also notify their sex partner(s), so they can receive testing and treatment if needed. It is important to take all of the medication prescribed, even if symptoms go away during treatment. Follow-up appointments are necessary to ensure that the treatment has worked and to monitor for any complications.